Containers of the above type have traditionally been produced in metal, and have been widely used for such contents as paint, drinking chocolate and cornflour.
Versions in plastics material have been manufactured, and hitherto they have been produced by welding together two discrete mouldings. The reason for this two-piece construction is the inward overhang of the top flange or rim. If known injection moulding methods are employed, it has been considered impossible to arrange it so that the inside male core can be extracted. The opening is too small to permit any form of collapsible insert. Blow moulding might offer a solution, but the problem with the rim has not been solved.
It is the aim of this invention to overcome this difficulty and to enable such a container to be made by blow moulding.